A variety of exit devices are commonly used with conventional doors. Typically, doors include an inactive stile and an active stile. Generally, the inactive stile is connected to a doorframe with hinges so that the door can move between open and closed positions. In certain applications, the active stile houses vertically concealed rods and latches, which extend into and retract out of the doorframe to lock and unlock the door. A midrail generally extends between the active and inactive stiles. Exit devices are commonly installed in a recess in the midrail and therefore have a relatively low profile, which provides a more aesthetically pleasing door. This is particularly desirable in applications in which the exit devices are installed on the front or in the entryway of public buildings. The relatively low profile of the exit devices also reduces the presence of the exit device in the door opening, maximizing the opening available for travel through the doorframe which is particularly desirable in cases such as handicap access. Additionally, the relatively low profile of the exit devices reduces the exposure of the exit device to contact and thus potential for damage.
A large number and variety of people, including the handicapped, children, and the elderly operate conventional exit devices. Additionally, exit devices are commonly designed to be easy to operate to provide rapid building egress during emergencies, such as, for example, during a fire or a natural disaster. For these and other reasons, many conventional exit devices include a pushbar, which is located between two end caps. To open and/or unlock the door, a person simply depresses the pushbar.
Typically, exit devices and doors are purchased separately and the exit device is installed in the door immediately before or even after the door has been installed in the doorframe. Generally, the exit device is installed in the midrail adjacent to the active stile and a filler is used to enclose the remaining portion of the midrail that is generally adjacent to the inactive stile. Accordingly, if the filler or the recess in the midrail is incorrectly sized, the exit device may not fit properly in the midrail and may not operate correctly because of interference between moving parts in the exit device. Conventional exit devices have attempted to minimize the potential for interference by minimizing the travel distance of the moving parts in the exit device and the midrail or filler. In particular, conventional exit devices are often designed to minimize the projection of the internal latching mechanism in the dogged or extended position, which in turn reduces the mechanical advantage that can be achieved by depressing the pushbar.
Exit devices are generally installed on the left or right-hand sides of doors depending upon the swing of the door and the entryway. It is therefore desirable for exit devices to be able to be usable in either a right-hand or a left-hand application. In addition to the above mentioned design considerations, exit devices that are easy to manufacture, easy to assemble, durable, and inexpensive are highly desirable for obvious reasons.